I only see uses of capacitive sensor to detect touch. But I wonder if I can calibrate a capacitive sensor to detect if a person is close enough, even if the person is not touching it.
I intend to use it with a RFID tag or a BLE to send information if there is a person close to it.
Update with more details: I want solve the problem of determining, cheaply, if a person is sitting on a chair. I already asked a question about this problem here: Can I use a RFID reader to check if there is an physical obstacle between it and the tag? through a particular way of solving this problem. Now I am asking about another way of solving it. It is not relevant if I will use a RFID tag or not. I understand there are multiple ways to solve the final problem, but now I am interested in knowing especifically if I can use a capacitive sensor to detect a person proximity without touch.